This development relates in general to thermoplastic composites and in particular to composites containing lignocellulosic materials.
Various industries are looking at additive materials to improve the properties of thermoplastics. In particular, there is a need to improve the properties of extruded plastics at competitive prices, while conserving materials and shortening process times. For example, in the past U.S. Pat. No. 5,948,524 to Seethamraju et al. describes combining wood and polymer together, then heating the mixture to melt the polymer.
A common problem is the expense of using pure material, both in terms of the environmental costs and the economic costs of producing thermoplastic composites. U.S. Pat. Nos. 6,270,883 and 6,730,249 to Sears et al. describe thermoplastic composites using high purity and expensive cellulose (where the cellulose is the most thermally stable constituent in wood).